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Re: Raycasting 3D demo disk



aiiadict@gmail.com wrote:
David Schmenk wrote:
Here for your enjoyment is a technology preview/demonstration of a
raycasting and rendering algorithm I have developed as part of my Apple
II 30th birthday-retro-game-just-because-I-can thing.

would be cool if you could add a couple of lines to the beginning of
your
code, and make textures/maps relocatable... IE load them wherever
you want (not in GR screen, your demo code, etc)...

then I could choose somewhere besides $2000 for maps, and still
use the HGR screen for the editor.. no disk accesses to reload
the map after HGR access would speed it up.

Rich


Look at the demo loader program. There is a pointer to the map level at $300, along with the map width in bytes at $302. The texture map base pointer is at $306. Heck, from the source:
;
; GLOBAL PARAMETERS
;
MAPLVL	=	$0300	;POINTER TO MAP LEVEL
MAPSTRD	=	$0302	;MAP WIDTH IN BYTES
RETCODE	=	$0303	;RETURN CODE 0=EXIT FF=ESC
TEXBASE	=	$0306	;BASE ADDRESS FOR TEXTURES
PLAYERX	=	$0308	;X COORD OF PLAYER 8.8 FIX PT
PLAYERY	=	$030A	;Y COORD OF PLAYER 8.8 FIX PT
PLAYERA	=	$030C	;VIEW ANGLE OF PLAYER 0..255

You can set theses values to locate the maps and player position wherever you like. The code is currently assembled for $6000 so that needs to stay.

Dave..